Grinding-machine.



0. SMITH.

GRINDING MAGHINE. APPLICATION FILED r32. 11, 1907.

Patented Aug. 10, 1909.

flu: 39

6. SMITH.

GRINDING MACHINE.

uruonrox FILED 11:11.11, 1907.

Patented Aug. 10. 1909.

3 SHEETS-SHEET 2,

. ing machine by which to reduce t be thickness of bars and surfaces by grind ng both sides of a metal bar at one operation, espe- GHETWOOD SMITH, OF WORCESTER, MASSACHUSETTS.

Specification of Letters Patent.

GRINDING-MACHINE.

Patented Aug. 10, 1909.

Application filed February 11, 1907. Serial Nofitfia'li'l.

To all whom it may concern:

Be it known that I, Cnn'rwooo Surrn, a citizen of the United States, residing in \l'orcestcr, county of Worcester, and State of Massachusetts, have invented an Improvement in Grinding-Machines, of which the following descri tion, inconnectien with the accompanying rowing, is a specification, lilte letters on the drawing representing like parts.

This invention has for its object the production of a novel macl1ine, oi1 which to simultaneously grind metal bars on both sides, instead of grinding said bars first on one and then on the other side, as commonly done, the grinding being effected by my invention on a constant curve irrespective of the grinding wheels.

rior to my invention, I am aware that grinding wheels carried by shafts having a 'common center of rotation have been employccl' for grinding parts of articles, the articles being thrust into the space between the faces of revolving wheels or flanges.

In my study for the production of a grindcially bars to be used for the blades ofi skates or in the formation of any tools where v the sides are to be tapered or ground on a curve, I have discovered for successful and practical work that the axes of the grinding wheels should standat an an le one to the other to intersect. I have 1lustrated the rinding wheels in my invention as of cup ing machine:.F1gl 2 isa partial end view of shaperind beveled at their acting edges, to present frusto-conical rinding faces, the

, axes of the wheels being set at such an angle 40'.

that the adjacent portions ofthe rinding faces are substantially parallel vfiien the wheels are einplo ed to, rind the blade beiugracted upon. he bla e bein' acted upon is supported at its lower edge a suitable restbwhich is made vertically ad ustable.

, Figure Lisa plan view of my novel grindthesznachine Fig. 3,:is an elevation of the left hand half of the machine shown in Fig. Land Fig. 4 is a detail showing means for adusting the work rest.

' he tl rame of the machine, as I have hereinchesenjto. illustrate the same, comprises a bsse' partorway' 1i h exfrom a central gr asset :padglB Y the shafts l), D to the inner ends of which are connected in usual manner grind ers shown as cup wheels l), I), The foot of each stand is fitted over a stud C rising from one of said carriages, and each of said stands has, as shown, curved ,SlOis C til re ceive guiding bolts (3 carried by said car riages, so that the bearing stands 0 may be turned more or less about said stud (1 to vary the angular position of the shafts D,D' wit '1 relation to each other, as may be de sired, according to the particular shape of the article to be ground, the adjustment of the shafts by turning the stands placing the beveled gr frusto-ronimll rinding faces (1,0" otthe up-sln1ped grintin wheels at the proper distance apart, said faces, when in action, being substantially parallel one to .the other at the grinding point, see Fig. 1.

Each carriage at its under side below the stud C has a threaded boss E war is en.-

.tered by the thrcaded part of a'screw E ground or to compensate for wear of the grinders in use. Such adjustment of the wheels longitudinally of their axes does not change in an Way the relation of the frusto conical rin ing faces, as will be obvious, and it will be clear that no matter how much the grinding faces wear away the surface ground 'Will have a constant curvature. That is, the curvature of the surface of the grinding face which contacts with the work will have a constant radius. The wearing back of the frusto-conical face of the grinding wheel is compensated for by setting up the wheel lon itudinally of its axis. L

.Eacirshfift D has a like belt pulley D that receives a belt by which to rotate each shaft at the desired specd. Below the smce in line with the acting edges of the grin crs, I have provided a work rest 6' on which may rest the ed e of the stock or blade which is to be ground simultaneously at its opposite sides, while being fed between the opposed acting edges (i, a of the grinders, This work rest is carried by a rod 1 screw threaded to receive the threads at the interior of the hub of atoothed nut e Sl'lUWIl in Fig. 4 as having beveled teeth that are engaged by-thc teeth of a beveled inion e on the short shaft 0' in the base 0 the machine, said shaft having a hand wheel 0 the rotation of which raises or lowers the work rest according to the reqt'iirements o-f thc stock bein ground,

Having ully described my inventioinwhat l claim as new and desire to secure by Let ters Patent is 1. In a grinding machine, two grinding wheels, rotary shafts carryin the same, hearings to sustain the longitudinal axes of said shafts in angular position one with relation to the other, means to adjust longitudinally=said hearings and the shafts carried thereby, and separate means tovary the angnlarity of the shafts: the means for effecting longitn'dinal adjustment being operative independently the ungularity.

2. In a grinding machine, two rot grinders having their axes lntciz having frusto-conical grinding means operative while the grinders are operating to move the "'rinders toward each other longitudinally 0. their axes to take up wear of t 1e grinding faces, the latter grinding opposite sides of thework with a constant curvature irrespective of wear of the grinding faces.

3. In a grinding of the nit-ans to vary atable cting and machine, two rotatable grinders having their axes intersecting and having frusto-conical grinding faces, means tovary the anguIarity of the axes of said grinders, and separate m'eans operative while the grinders are operating'to move them toward each other longitudinally oftheir axes, the grinding faces operating to grind opposite sides of the work with a constant curvature irrespective of wear of the said grindingfaces.

In testimony whereof, name to this specification, two subscribing witnesses. i

CHETWVUOD SMITH.

I have signed my in the presence of :t'aces, and 

